Processing of Rhubarb and Determination of Five Free Anthraquinones in Raw Rhubarb and Stewed Rhubarb

[Objectives]To determine the content of five kinds of free anthraquinones in raw rhubarb and stewed rhubarb by HPLC,and compare their content difference,so as to reveal the change rule of material basis before and after processing of traditional Chinese medicine.[Methods]The content was determined by HPLC with Thermo BDS HYPERSII C18 column(4.6 mm×250 mm,5μm)as chromatographic column and methanol-0.1%phosphoric acid(85∶15)aqueous solution as mobile phase;the detection wavelength was 256 nm,the flow rate was 1.0 mL/min,the column temperature was 30℃,and the injection volume was 10μL.[Results]Aloe-emodin,rhein,emodin,chrysophanol and emodin methyl ether showed a good linear relationship in the linear range of 0.0207-0.414(R2=0.9999),0.1721-3.442(R2=0.9996),0.0203-0.406(R2=0.9999),0.148-2.96(R2=0.9998)and 0.164-3.28(R2=0.9993),respectively;the content of aloe-emodin decreased by about 8.26%,and rhein decreased by about 9.21%;the content of emodin increased by about 16.44%,chrysophanol increased by about 16.12%,and emodin methyl ether increased by about 20.01%,indicating that the processing technology had different effects on the components of rhubarb.[Conclusions]The content of five free anthraquinones in rhubarb was affected to different degrees after processing,and this method could be used as a quality control method for rhubarb and its different processed products.

Determination of Total Anthraquinone and Free Anthraquinone in Different Processed Products of Rhubarb

[Objectives]The content of total anthraquinone and 5 free anthraquinones in different processed products of rhubarb were determined.[Methods]Using emodin as the reference,the concentration of 1%magnesium acetate methanol solution was used for color development,and the absorbance was measured at 516 nm wavelength;the mobile phase was methanol-0.1%phosphoric acid(76∶24)aqueous solution,the detection wavelength was set at 256 nm,the flow rate was 1.0 mL/min,the column temperature was 30℃,and the sample size was 10μL.[Results]The content of total anthraquinones in rhubarb was determined by UV spectrophotometry.The linear range was 0.98-23.52μg/mL,R2=0.9993,the average recoveries were 100.12%,99.66%and 99.15%,with RSDs of 1.58%,0.94%and 1.41%,respectively.The linear ranges of emodin,emodin,emodin,chrysophanol and emodin methyl ether were 0.0207-0.414(R2=0.9999),0.1721-3.442(R2=0.9996),0.0203-0.406(R2=0.9999),0.148-2.96(R2=0.9998)and 0.164-3.28(R2=0.9993),respectively.[Conclusions]The contents of total anthraquinones and free anthraquinones in different processed products of rhubarb were determined by UV spectrophotometry and HPLC.The method can be used for quality control of rhubarb and its different processed products.

Effect of EuCl_3 on Hairy Root Growth of Cassia Obtusifolia and Production of Its Active Principle

Treated with extremely low EuCl 3 (0 001, 0 01, 1 0 mg·L -1 ) in MS medium, the hairy root growth of Cassia obtusifolia was inhibited. The inhibition was strongest at the treatment with 0 001 mg·L -1 EuCl 3, and the dry weight of hairy roots was 22% lower than that of control. Treated with rather low EuCl 3 (10 mg·L -1 ) in Murashige and Skoog(MS) medium, the hairy root growth was enhanced, and the dry weight of hairy roots was 27% higher than that of control. In the each treatment with 0 001 to 1 0 mg·L -1 EuCl 3 in MS medium, the total content of six free anthraquinones was lower than that of control. While treated with 10 mg·L -1 EuCl 3, the total content of six free anthraquinones was 26% higher than that of control, 97% higher than the treatment of 1 0 g·L -1 EuCl 3. Treatment with 10 mg·L -1 EuCl 3 in MS medium enhances the growth of hairy root of Cassia obtusifolia and improves the total content and production of six free anthraquinones in them.